Found someone to do this, so far estimate is £199 for 3 bed semi, government pay the rest - can't be bad eh - will save me £88 a year so pays for itself fairly rapidly.

Will save fuel bills and help get grant for solar if I do the loft too, to 270mm, .[/quote]

I had my house checked by a company who were offering to do it for £99 - they did a survey, which was free and found that it already had insulation. I'll find the phone number tonight and post it here tomorrow.

Had a survey done last month and they found that the cavity had bits of rubble in a few places so they would not do the job, spoke to someone else who I know who used a different company who did not do a survey and it turned out they to had rubble/rubbish in the cavity and it had left them with a severe damp problem so be careful who you use.

We had our house done this summer - obviously waiting for the winter to find out if it's effective or not. But they were good at plugging all the holes with matching mortar! However the important thing is to get a guarantee and not one from the installer who could go broke in the meantime. Our installer was registered with The Cavity Insulation Guarantee Agency who provide the 25 yr guarantee. I think you'll find their registered installers on their website at www.ciga.co.uk. I won't bother with giving you our installer's name as we're in deepest Essex!

I know the main aim of the wall cavity insulator is to make the house warmer, but does it help to keep out the noise? The baby next door is driving my Missus insane so cutting out the crying would be good.